The present invention relates to a WC water tank, and more particularly to a device for the reduction of rinsing water consumption in WC water tanks which include a closing member formed as a buoyant element.
It has been required during the rinsing of the WC-tank that determined smallest amounts of water be released to prevent formation of crust and plugs in the open sewer system. Up to now about 10 liters of water has been considered as the smallest amount which should automatically flow from the tank upon the release of the latter. However, in order to reliably prevent contamination of the sewer system urine rinsing has been also unconditionally required.
For obtaining such discharge water amounts in conventional WC tanks a closing or locking element has been utilized, which closing element has a sealing which closes an outlet opening of the tank by continual hydrostatic pressure acting on the closing element. If the closing element is lifted upon the actuation of the rinsing knob the hydrostatic pressure is ceased and the closing element is lifted to permit the water drainage. Thereby the outlet opening remains open until the water tank is emptied. Then the closing element, normally an elastic ball, falls onto the outlet opening again and closes the latter so that water which fills the tank builds up hydrostatic pressure again until the next rinsing.
Due to the fact that drinking water reserves are to be conserved it has been necessary to reduce water consumption wherever necessary.